Covered the ground completely

The Literary Digest of Sept. 2, 1921 published a letter from Carl G. Gowman of Detroit, Michigan, relating a fall from the sky of a substance resembling blood in southwest China on Nov. 17 (1920?). “It fell upon three villages close together, and was said to have fallen somewhere else forty miles away.” In one of the villages, the substance “‘covered the ground completely’”, and was found on roofs and the ground. The spots “did not dissolve in several subsequent rains,” and that “nothing was in bloom” at the time, so it was not pollen.